The DPtoLP function converts device coordinates into logical coordinates. The conversion depends on the mapping mode of the device context, the settings of the origins and extents for the window and viewport, and the world transformation.
BOOL DPtoLP(
HDC hdc, |
// handle to device context |
LPPOINT lpPoints, |
// pointer to array of points |
int nCount |
// count of points |
); |
If the function succeeds, the return value is nonzero.
If the function fails, the return value is zero. To get extended error information, call GetLastError.
The DPtoLP function fails if the device coordinates exceed 27 bits, or if the converted logical coordinates exceed 32 bits. In the case of such an overflow, the results for all the points are undefined.